Most of these are non-fleshy seeds and they wait in their capsules or seedheads for one of the agents of dispersal to send them on their way: wind, water, and wildlife. I noticed that the capsules on the swamp hibiscus (Hibiscus coccineus) close up when wet and open wide when dry. Pine cones do this as well. I imagine they’ve evolved over time to adapt a strategy that works best for dispersal. The hibiscus seeds look like an offering of candy in a bowl, just waiting for a bird to come by and have a few.
|Seeds attached to fluff on Liatris|
|Fluffy seeds of little bluestem|
Some seedheads are puffy, each seed equipped with its own bit of fluff to carry it away. I think of these plants as hedging their bets: the puffiness alerts birds that the seeds are ripe and ready, but if the birds fall to notice them then the wind can be the means on which they travel. Some members of the Asteraceae family employ this technique but not all of them.
The black-eyed Susans (Rudbeckia), rosinweeds (Silphium), sunflowers (Helianthus) and coneflowers (Echinacea) are three members of the Asteraceae family that keep their seeds tightly held in the dried flowerhead. If you’re cleaning seed, they are hard to get out! Birds are required to pry the tasty seeds out (and of course they are pretty good at it by now).
|Helianthus, seeds on left already taken|
|Some stems come with bugs too|
|Turtlehead (Chelone glabra)|
While I enjoy watching the birds at the bird feeder, I’m also happy to know that these seeds are available for them too. I do occasionally startle a pair of goldfinches feeding among the dry stems (never when I have the camera, of course).
Nature has been providing for them for thousands of years in this fashion, and I’m happy that my garden can contribute.